package com.dailywork.basepro.security.secret;

import javax.crypto.*;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.Security;

public class EncrypDES {

    // KeyGenerator   提供对称密钥生成器的功能，支持各种算法
    private KeyGenerator keygen;
    // SecretKey   负责保存对称密钥
    private SecretKey deskey;
    // Cipher负责完成加密或解密工作
    private Cipher c;
    // 该字节数组负责保存加密的结果
    private byte[] cipherByte;

    public EncrypDES() throws NoSuchAlgorithmException, NoSuchPaddingException {
        Security.addProvider(new com.sun.crypto.provider.SunJCE());
        // 实例化支持DES算法的密钥生成器(算法名称命名需按规定，否则抛出异常)
        keygen = KeyGenerator.getInstance("DES");
        // 生成密钥
        deskey = keygen.generateKey();
        // 生成Cipher对象,指定其支持的DES算法
        c = Cipher.getInstance("DES");
    }

    /**
     *      * 对字符串加密      *      * @param str      * @return      * @throws InvalidKeyException
     *      * @throws IllegalBlockSizeException      * @throws BadPaddingException
     */
    public byte[] encrytor(String str)
            throws InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
        //   根据密钥，对Cipher对象进行初始化，ENCRYPT_MODE表示加密模式
        c.init(Cipher.ENCRYPT_MODE, deskey);
        byte[] src = str.getBytes();
        //   加密，结果保存进cipherByte
        cipherByte = c.doFinal(src);
        return cipherByte;
    }

    /**
     *      * 对字符串解密      *      * @param buff      * @return      * @throws InvalidKeyException
     *      * @throws IllegalBlockSizeException      * @throws BadPaddingException
     */
    public byte[] decryptor(byte[] buff)
            throws InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
        //   根据密钥，对Cipher对象进行初始化，DECRYPT_MODE表示加密模式
        c.init(Cipher.DECRYPT_MODE, deskey);
        cipherByte = c.doFinal(buff);
        return cipherByte;
    }

    /**
     *      * @param args      * @throws NoSuchPaddingException      * @throws
     * NoSuchAlgorithmException      * @throws BadPaddingException      * @throws
     * IllegalBlockSizeException      * @throws InvalidKeyException
     */
    public static void main(String[] args) throws Exception {
        EncrypDES de1 = new EncrypDES();
        String msg = "郭XX-搞笑相声全集";
        byte[] encontent = de1.encrytor(msg);
        byte[] decontent = de1.decryptor(encontent);
        System.out.println("明文是:" + msg);
        System.out.println("加密后:" + new String(encontent));
        System.out.println("解密后:" + new String(decontent));
    }
}
